A variety of resonant tunneling devices have been constructed and/or proposed in the literature. Examples of these structures are: a resonant tunneling emitter transistor; a hot electron transistor; and a quantum well resonant tunneling base transistor. One major problem is that all of these structures have a low peak-to-valley current ratio and are mostly functional at low temperatures. Further, it is difficult to contact theses structures (e.g. base, emitter, collector or gate, source, drain) without incurring unacceptable amounts of leakage current between contacts.
Resonant tunneling devices have a potential of replacing conventional transistors in some applications, such as logic circuits, if they can provide non-monotonic characteristics that can be utilized to build smaller logic circuits. The limiting factor currently in these structures is that they are being fabricated in exotic material systems that can not be combined with conventional technology.
Thus, there is a need to provide small resonant tunneling devices with non-monotonic characteristics, which can be combined with existing technologies.
It is a purpose of the present invention to provide a new and improved resonant tunneling field effect transistor.
It is another purpose of the present invention to provide a new and improved resonant tunneling field effect transistor which can be easily integrated with existing VLSI and ULSI technologies.
It is still another purpose of the present invention to provide a new and improved resonant tunneling field effect transistor which can be combined with existing technologies to provide high performance and smaller dies for logic circuits.